Cast-metal container



May 8, 1923. 1,454,291

- J. G. LEHMAN CAST METAL CONTAINER Filed Feb. 1. 1921 JOHN GEORGE LEHMAN, OF BETHLEM, PENNSYLV, ASSIGEYOR T BEEN; ,1

FOUNDRY & MACHINE COMP, 0F BETHLEHEM, PENNSYLVA T1033 OF PENNSYLVANIA.

A eoaroae- CAST-METAL CONTAINER.

Application filed February 1 1921. Serial No. 441,5e3.

T0 all wkom it may concem:

Be it known that 1, JOHN Gnonoa LEHMAN,

a citizen of the United States, residing at Bethlehem, in the county of Northampton and State of Pennsylvania have invented a certain new and useful ast-Metal Container, of which the following is a specififrom fluid in cation. v

My invention relates to kettles or other containers, in which heat treatment is to be carried out.

A purpose is to provide a cast metal kettle, pot, pan or other vessel having coils of pipe withinthe surrounding cast metal walls and welded into union with the metal of the walls, with the object of transferring as large a percentage as possible of the heat the pipes mto the vessel contents.

A further purpose is to provide a cast metal,vessel with a coil of pipe within its walls and having spuds, ties or other fastenings of material having a greater tensile strength than the cast metal to strengthen the vessel.

Further purposes will appear in the specification and in the claims. I

I have preferred to illustrate my invention by a. few only of the forms in which it .mg my invention. Figure 4 is a side elevation of aco'il like that in Figure 3, but having termlnals for.

use as the bottom of a vessel.

Figure 5 is a top plan view ofa ser entine such as may be used to lie' within a at bottom or flat-sided wall or may be bent to lie Within a curved wall.

Figures 6, 7 and 8 are broken enlarged [sections showing diil'erent separating and .fastening devices and their anchorages.

Similar numerals indicate like parts.

This application is a continuation in part of my application for'method and apparatus for controlling expansion, filed July 24, 1919, Serial No. 312,965.

In the treatment of various liquids, particularly in the practice of chemical processes upon a commercial scale, it is ver desirable to control the temperature 0 the vessel in which the mixture is being treated by the introduction of a heating medium, such as steam, hot Water under pressure or oil or a cooling medium such as brine, water, or other cooling medium within the walls at close intervals.

Though the invention herein claimed is the article, I consider it important to explain the conditions of manufacture.

It has proved impracticable to cast passages within the shell of the vessel and considerable difiiculty has been experienced in casting pipe (by which I mean to include passage linings generally, which are distlnct in those Walls so as to provide for proper fiow therethru. It is comparatively easy to bend the pipe to the shape desired but as soon as the molten metal is poured upon the bent or coiled pipe the latter is distorted by reason of the sudden expansion taking,

rom the metal cast about them) withand, notwithstanding this, the coil has tended to rock and shift to such an extent as to lie too near the surface at points, interrupting the cast finish of the vessel or interfering with an intended finishing cut and causing it to heat irregularly and uncertainly. v

I aim to overcome these defects and to secure a thinness of wall and an intimacy of contact which result in a very high eficiency of heat transfer.

In Figures 1 and 2 I have illustrated a kettle 10 made up of a coil of pipe shown as having inlet 11, outlet 12, and interven- Ell - ing better ing'spirals 13, ll. The spiral l3 is'of hell cal form and the spiral 14.- may be of any combination oi? helical and fiat spirals or, where a flat bottom is desired, of purely fiat form.

The coil is cast within the wall of the vesseland, as it is quite desirable in most-cases to preserve the skin of the casting upon the interior a the vessel, the interior surface 15 is preferably not tool finished; though this may be done, if desired. The preserva tion of the skin of the casting upon the exterior surface 16 is not so important, though it also is usually not disturbed by a machine cut.

After the pipe has been bent to the required spiral or other shape, I unite its coils-or bends for the several purposes of preventing sagging, because of their weight, to restrict excessive or dispro ortionate expansion either radially or axially with respect to the vessel on account of the molten metal, and to increase the strength of the vessel against bothv shock and strain.

In what T regard as the best form, the coil sections are united at intervals-by spuds '17 preferably of steel or wrought iron, giving high tensible strength.- They are welded at their ends to the pipe with a minimum of pipe engagement. ll prefer to place those spuds at rather frequent intervals to maintain close expansion control over the pipe. These support the pipe against sag= ging and also, while accommodating expansion, maintain the spacing of the coils when the molten metal tends to spread them.

Prior to casting in this first form as well as inthe other forms of m invention illustrated, I very much pre or to pickle the pipe, in order to permit much more intimate contact of the final metal of the cast ing with the pipe, than would otherwise re sult. This causes the molten metal to form a weld with the pipe, greatly increasing the heat conductivity and the strength. v

Though there is not the same extent of heat-transferdesirability of intimate weld contact of the cast metal and the spuds,- or other ties or spacers used, as with the pipe coils, in practical operation the 'ickling is done with the ties or spacers in p ace, securheat transfer and greater strength.

Tn Figures 3 and 4.- the same method of manufacture described in connection with Figures 1 and 2 is ap lied to a nearly conical spiral which in *igure 3 is intended for casting within a comparatively shallow pan and in Figure l is given a vertical inlet 11' for casting within a separable bottom (of which the cast metal is dotted about it) for a large vessel. The two spirals are the same except for the direction of inlet connection.

In Figure 5 the same method of attachinteger ment of adjoining pip'e sections is applied to a serpentine section 18 normally intended to lie in a single plane or capable of being bent to conform to a cylindricalvessel wall or to various othercontours.

The location of the walls of the vessel with respect to the coil of pipe is well shown in Figure 6:

Tn addition, Figure l; shows another useful feature in construction of the vessels in that T anchor the coils of pipe through the mold 19. As the mold isnot ordinarily strong enough to afiord proper stifi'ening and support for the anchorage, T may pass the anchors 20 not only through the mold but through supporting devices, here connected in the. form of strips 21, outside or within the walls of the mold. These anchors 20 are hooked at oneend, as at 22 about the spuds, (rather than about the pipe, to reduce the permissible wall'thickness) and are secured within the strips 21, by nuts 23. They may anchor occasional co 'nections only.

hese anchorages are normally supported and held upon the outside for two reasons.

The inside wall is the one primarily to be protected, making it desirable to prevent the pipe from approaching the inside wall 15 of the kettle closer than a predetermined distance set by the anchors also the assage of the anchors through the wall on t e side upon which they are supported would, otherwise, damage the inner wall. After the casting is completed the projecting ends of the anchors are cut oil leaving the stub ends exposed. This would be objectionable on the inside of the vessel because of the effect of the exposed metal upon the contents of the vessel.

It will be noticed that the assage of the hooks through the mold wall and through the supporting strips 21 has a tendency to prevent excessive movement of the pipe up and down.

In Figure 7 the coils of pipe are not united as in Figure 6 but are held. against undue movement toward the interior wall 15 and toward each other bypreferably cast iron separator blocks .24; which engage with the adjoining surfaces 25 of the pipe coils and prevent radial movement of the pipe at the same time that they exert some restraint laterally with respect to the anchors 20 by reason of the passage of these anchors through the mold and through any desired limiting supporting plates. They extend to the left beyond the pipe centers.

The bolts are here shown as separate from the blocks and as provided with heads 26' fitting within recesses in the blocks. V

In the form shown in Figures 1 to 6, spuds hold the coils of pipe in position initially, separating them against collapse when placed in the mold, limiting the sepal Ell meager ration of the adjoining coils by their firm hold upon the coils and stiffening the com pleted vessel. The anchorages 20, 20 have a little strengthening and stifi ening efiect but are of advantage almost exclusively in the manufacture of the vessels.

Spot welding has proved quite effective in uniting the spuds to the coils, giving sufficient strength for the purpose, thoughI contemplate using whatever may be required in a particular case to give firm union.

The location of the spuds between the coils, as distinguished from inside or outside of the coils, enables me to cast a thinner wall, giving better heat transfer conditions, and the individual connections thus supplied form each pair of coils into an efiective spiral beam, substantially free from initial stresses and, because of the connections used separate from those uniting with the next coil, unaffected by the stresses or posi tion of the rest of the structure, yet all combining to provide a maximum of strength with a minimum of material.

in Figure 7 the separator blocks perform an initial separating function but offer little restriction against expansion of the coil axi-' ally of the vessel when the hotmetal is poured upon the coil. Here again, the spacing devices 2% may be confined wholly to the portion of the wall between the pipes.

in Figure 8 the ties 27 unite adjoining coil sections against separation but offer little support against collapse of the coil sections when they are initially placed within the mold. Though I do not regard the twisting as of great importance it is desirable to twist the ties together or at least to cross them as shown at 28; and this twisting or crossing facilitates the engagement of the ties by anchoring hooks 20. In this form also, the ties are in effect individual, even though the wire used be extended to form other connections between coils above and below a particular pair under consideration; and the use of wire, with its high tensile strength gives a minimum of extra width on each side of the pipe--toward the inner and outer walls.

In all of the forms, the fastenings 20 are or may be individual to the single connection to which they are attached, capable of separate adjustment in position and permissibly much fewer in number than the ties to which they are connected. There is considerable advantage in the facility oll'ered for anchoring each pair of coils, or as many pairs as desired, separately through the lateral wall of the vessel and mold, lacilitating correction of coil alignment without chan e in the character of devices used and. simp ifying both construction and operation.

In the form shown in Figures 1-6, it will be noted that the cross section of the pipe itself forms part of the reinforcing structure considered transversely of the coil I length and parallel to the outer and inner walls.

In all of the forms, the interconnection of the several coilsforms a continuous beamconstruction. Each pair of turns with the ties, members or supports, forms a beamin itself and in its entirety reinforces the next adjoining beam (which will ordinarily have one turn of pipe in common with the first). The lateral ties strengthen slightly in re-' sistance against fracture.

The welded contact between the walls of the vessel and the included pipe greatly increases-the efiiciency of heat transfer. I have secured an etliciency of more than 90%. The weldedv contact between the ties and the metal of the vessel walls also slightly improves the efiiciency of heat transfer, but is much more useful in obtaining a maximum stiffening and strengthening effect from these materials, whose tensile strength as well as resistanceto fracture will ordinarily be. much higher than that of the cast metal.

I desire to include herein not only the structures shown as examples but the various other forms which will be suggested to those skilled in the art by my disclosure and discussion of principles herein and which. come within the reasonable spirit and scope of my invention.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is: i

1. A cast metal vessel having within the thickness of its walls a spiral tube, in combination with supports for the turns of the spiral, one from another, of different material from the body of the vessel strengthening against compression and stiffening against transverse fracture between the turns.

2. A cast metal vessel having within the thickness of its walls a spiral tube, in com.- bination with means within the walls uniting the turns of the spiral and strengthening the vessel. Y

3; 'A cast metal vessel having Within the thickness of its walls a spiral tube, in combination with means within the walls uniting the turns of the spiral and strengthening the vessel, said means and tube welded to the metal the cast container.

4;. A cast metal vessel for heat treatment having coiled pipe within its walls and ties between the turns of the coil.of greater tensile strength than the cast metal.

5. A vessel for conducting heat treatment, comprising a coiled pipe having the adjoining faces of the coils united, in combination with cast metal surrounding the coils and the uniting means.

6. A vessel for conducting heat treatment,

comprising a coiled pipe having the adjoina I :t ,eee,ee1

emit the lateral facet; of the pipe free from this union, in'comloinetion with 3], cast metal Well about the pipe atml Welded thereto,

Z. A vessel for. heat treatment comprising cast metal Wells, e coiled pipe Within the Wells, and ties for the pipe extending leterelly of the Walls to the outside of the vessel.

8. A vessel for heet treetmemt comprising cast metal walls, a coileol pipe Within the wells, fastening devices between the turns oic' the pipe, and ties for the pipe extending laterally of the wells to the outside of the vessel.

JGHN GJEURG-E Lemme. 

